A conventional clip is widely used to holding a stack of papers or other kinds of sheets togather. It is not only very convenient but also economical to use a clip. However, as the clipped stack being thick, a clip may deform too much to be able to hold the stack of sheets or papers steadily. The present invention is concerned with this problem, and the general aim of this invention is to provide a renovated clip with triangular cross section which not only reserves the convenience and economy of a clip and eliminates the shortcoming of a conventional clip when clipping a thick stack of papers or sheets, but also can be shaped to be more versatile than a conventional clip under various clipping requirements.